Diarrhea

• Onset: 20 - 50 Gy

  
  

  early onset: within 24 hours after RT

  
  

  late onset: more than 24 hours after RT / 8 - 12 months after
• • Grade 1: < 4 stools per day over baseline / mild increase in ostomy output
  • Grade 2: 4 - 6 stools per day over baseline / moderate increase in ostomy output
  • Grade 3: > 7 stools per day over baseline, incontinence / severe increase in ostomy output
  • hospitalization indicated
  • limiting self care ADL
  • Grade 4: life threatening, urgent intervention indicated
  • Grade 5: death
• Physiology:

  • Acute:
  • Crypt stem cells affected by radiation → atrophy of villi in small intestine
  • Loss of epithelial absorptive function → loss of water, electrolytes, protein, blood
  • Conjugated bile salts not absorbed → enter colon → deconjugated by bacterial flora → water retention and diarrhea
  • Result of hypermotility of bowels + loss of absorptive surface + decreased absorption of nutrients and bile salts + decreased / absent lactase → lactose intolerance 
• Physiology:

  • Chronic:
  • Vascular insufficiency due to damaged cells in blood vessels and connective tissue (onset 8 - 12 months but can occur years after treatment)
  • Mucosal ulcerations
• Chemotherapy agents:

  • capecitabine
  • 5 FU
  • irinotecan
  • leucovorin
  • small molecule oral tyrosine kinase inhibitors
  • immunotherapy
• Pharmacological management:

  • Goal: inhibit intestinal motility, decrease intestinal secretion, and increase intestinal absorption 
  • Loperamide (imodium - over the counter)
  • Slows GI peristalsis →  increase GI transit time, promotes water absorption 
  • Not for patients with suspected obstruction 
  • 2 tabs STAT, 1 after each movement 
  • Diphenoxylate / atropine (lomotil - prescription)
  • Slows GI transit time
  • Increase CNS side effects
  • Do not exceeds 8 tabs in 24 hours 
  • Bulk forming agents (psyllium fiber, methylcellulose, pectin)
  • Absorbs water, enhance stool bulk
• Grade III and IV management: usually hospitalization

  • Lab tests: CBC, electrolytes, creatinine, stool analysis
  • Nursing: vital signs, IV hydration
  • Prescription: octreotide (blood sugar regulation)
• Non pharmacological management: non urgent grade 1

  • encourage:
  • 10 - 12 cups of clear fluid
  • soluble fiber
  • small frequent meals
  • avoid:
  • spicy and greasy foods
  • alcohol
  • sorbitol (candy)
  • skin care
  • sitz bath
  • saline rinse
• Watch for:

  • dehydration: diarrhea > 7 times a day → may need IV hydration
  • sores around rectal area → sits bath, open air, avoid tight clothing
  • malnutrition
  • sepsis
  • blood in the stool
  • neutropenia
  • reaction to antibiotics
  • fever
  • some chemo can exacerbate diarrhea
• Seek immediate medical attention if:

  • temperature > 38 degrees celsius
  • bloody stools
  • severe cramping, acute abdominal pain +/- nausea and vomiting
  • dizziness, weakness, confusion, excessive thirst, dark urine
  • diarrhea or increased ostomy output not improving with recommended strategies